Surfacing machine



Aug' 16 1927 E. D. TILLYER ET Al. y

SURFACING MACHINE Filed Dec. 3, 1924 2 Sheets-Sheet 2 5 c}27 3 c 5l Z6 .50 l 35 3l 33 L o J A Z2 2f I9 v i lo i a Jui-J..

INVENTOR cigar D. '.Till er'. velsen LB er.

Patented Aug. 16, 1927.

UNITED STATES EDGAR D. TILLYER AND NELSON M. BAKER, OF SOUTHBBIDGE, MASSACHUSETTS, AS-

, f 1.639.012 PATENT OFFICE.

SIGNORS T0 AMERICAN OPTICAL COMPANY, SOUTHBBIDGE, MASSACHUSETTS, A VOLUNTARY ASSOCIATION OF MASSACHUSETTS.

SURFACING MACHINE.

Application iled December 3, 1924. Serial No. 753,650.

This invention relates to improvements in surfacing machinery and has particular reference to the provision of an improved machine for forming and finishing spherical surfaces on lenses and lens blanks.

An important ob'ect of the invention is to provide a lens sur acing machine in which the curvature of the lens surface is generated by relative movement of the parts.

Another object of the invention is to provide such a device which will be adapted for the production of curves of different radii Without the necessity of changing the parts.

Another object is to provide such a device which may be used for producing either concave or convex surfaces of any desired radius.

Another object is to provide such a device which will be simple in construction, strong 2U and durable in service and elicient in use.

Another object is to provide such a device with an annular abrading tool operated in such a way that a, target blank may be pro. duced with perfect optical properties and better than has been possible with prior art devices.

With these and other objects in view the invention resides in the novel features of construction, combination and arrangement of parts hereinafter fully set forth, illustrated in the accompanying drawings and specifically pointed out in the appended claims.

1n the drawings forming a part of this specification Figure 1 is a vertical longitudinal sectional view through a surfacing machine embodying the invention.

Figure 2 is a fragmentary side elevation thereof.

Figure 3 is a top plan view.

Fi e 4 is a vertical sectional view on the l1ne 4--4 of Figure 3.

Figure 5 is a fra entary sectional view similar to Figure 1 s owing the tool and lens g in reversed position for the production of a concave lens surface.

Figure 6 is a fragmentary sectional view illustrating a modified form of tool support. Referring particularly to Figures 1, 2, 3

and 4, it will be seen that a main frame 10 has been provided in the form of a pedestal in vwhich is rotatable a ,spindle 11. The

spindle 11 is mounted in bearings 12 and ity of the spindle 11 is tapered asshown at 17 for the reception of a lens block 18 to which is secured in any desirable manner a l lens blank A.

. A sleeve 19 is a'djustably su ported upon the pedestal 10 and adapted or movement in a direction parallel with the axis of the spindle 11. In order to hold the sleeve in the desired adjusted position it is provided with a spring pressed plunger 20 which may be retracted through the instrumentality of a cam 21 operated by.a handle member 22. The pedestal 10 is provided with a plurality of recesses 23 into which the plunger 20 is adapted to be selectively seated, the purpose of this adjustment being to govern the radius of the curve produced upon the lens..

Extending outward] from opposite sides of the sleeve 19 to a jacent its upper end are a dpair of pivotal shafts 24 carrying T shape upwardly therefrom are a pair of arms 26, one of which is provided with recesses27 adapted to receive a spring pressed" plunger 28. A cross bar 29 connects the two rods,

bearing members 25. Seated in the, T shaped bearing members 25 and extending erative by a cam 30 and handle member 31 so that by use of the cam and plunger the cross bar may be moved to different selective positions to compensate for axial adjustment of the sleeve 19 which has been previously described.

A bearing boss 32 is formed at the central port-ion of the cross arm 29 and rotatable and slidable therein in a second spindle 33 supported in opposed rela-tion'to the spindle 11. The outer end of the boss 32 is thread'- ed as at 34 for the reception of 'an adjustable nut 35 which supports a pulley 36 carried by the spindle 33. The pulle A36 is ro`- tatable by the belt 37 and is weig ted downy by a ball or other suitable weight 38. The end of the spindle 33 adjacent the spindle 11 is suitably formed to receive an abrading tool 39 which is preferably formed with an annular working surface 40 of any suitable material. This abrading tool 39 may be formed of emery or it might be a metallic member charged with diamonds as is well known in the art, the latter being preferable for rough surfacing.

As best shown in Figures 2 and 4 an extension 41 is formed, preferably on the rear side of the pedestal l0, said extension forming a bearing 42 for the shaft 43. One end of the shaft 43 is equipped with a disk 44 having al diametric slot 45 therein for the' disk 44 carries a pulley 48 driven by a belt or any other suitable power connection 49 for the purpose of rotating the same.

In the operation of the device, a lens or blank A is mounted upon a block 18 which in turn is positioned upon the end of the spindle 11. The sleeve 19 is then adjusted longitudinally to its proper position so that the distance from the centre of the pivoting shafts 24 to the nished surface of the lens will be equal to the requiredradius of curvature. The cross arm 29 and its cooperating parts is then correspondingly adjusted so that the annular abrading tool 39 will rest upon the surface of the lens blank A whereupon both the spindles 11 and 33 are rotated through their driving members, and the upper spindle 33, at the same time oscillated through the instrumentality of the disk 44 and link 47. As best shown in Figure 4 the abrading tool 39 at the extreme end of its oscillating stroke goes over to the very edge of the lens blank A, and at its opposite extreme position it overlies the opposite edge of the blank. Thus in the course of the operation, the annular 4tool goes completely past the centre of the lens blank so that there is no possibility of bad spots being left at that point. As the tool wears down, or as the grinding of the blank progresses, the member 33 may be screwed down so that the tool will be held in properl contact with the blank surface. From this it will be seen that the curvature of the lens is generated by the relative movement of the One of the important results of this construction lies in the fact that the same abra'ding tool may be used for the production of any surface curvature merely by varying the position of the centre of oscillation. The amount of oscillation may be changed by; altering the position of the crank pin 46 in the disk so that the rotatable abrading tool will not go .too far beyond the edge of the lens blank when the latter is small in diameter.

In t-he device as illustrated in Figures 1,' 2, 3 and 4, it is shown producing a convex lens surface. By referring-now to Figure 5 it will be evident that concave surfaces may be formed with equally good results by reversing the operative parts, in other words, by mounting the abrading tool 39 upon the extremity of the spindle 11 and positioning the lens block 18 upon the extremity of the spindle 33. When the parts are thus associated it will be noticed that the lens block is oscillated over a tool'whereas in the pre vious form the tool was oscillated over the lens blank.

Referring particularly to Figure 6, a modied f orm of construction is illustrated wherein a concave lens surface may be produced While the lens blank is still positioned upon the spindle 11, the advantage being that the surface being operated upon is visible and therefore open to the inspection of the machine operator; whereas in the device. shown in Fi re 5 the surface being generated cannot Ibi; so easily viewed. In this modification a cross arm 50 is shown as connecting the'rods 26, the cross arm having 1ts central portion offset as at 51, to a. position below the points of connection of the rods 26. This construction makes it possible to get the pivotal shafts 24 in a position upon the lens blank A and still maintain a good firm bearing for the spindle 33. In this form the oscillation of the spindle 33 and its cooperating parts is produced in substantially the same way as in the previous form.

With the present invention', the objectionable features of the prior art surfacing machines have been overcome and it is now possible to produce either concave or convex surfaces of any desired radius with a high degree of accuracy. Also, such a machine as disclosed in the present application will perform rough grinding operations much more rapidly than has been possible with the prior art devices, especially when the annular abrading tool is formed of diamond charged material.

Obviously, changes may be resorted to in the minor details of construction and arrangement of parts, and the right is herein reserved to makesuch changes falling within the scope of the appended claims without departing from the spirit of the invention.

Havin thus described the invention, what a support, a slide movable on the support, is claim is: means for locking the slide in desired ad- 1. In a device of the character described, justedelpition on the support, a pair of $0 parall a a frame, a sleeve ad'ustabl mounted thererms ivoted on the slide, a cross on, a pair of space ara el arms pivoted member slidab y mounted on the parallel to the sleeve, a cross ar irml connecting arms, means for locking the cross member in the parallel arms, a rotatable spindle mountdesired adjusted position on the arms, a e'd in the frame, a second rotatable s indle spindle mounted on the su rt, means to 8l mounted in the crossbar in opposed re tion rotate said spindle, a spin mounted on to the first spindle, one of t e spindles bethe cross member infalignment with the rst ing adapted to support a lens lock, and spindle, means to rotate said spindle, a the other a -lens surfacing tool, and means grinding tool on one spindle, means for for reciprocating the arallel arms so as olding the lens on the other spindle, and IIl) to impart relative oscillatory motion bemeans to oscillate the parallel arms about tween the spindles whereby to generate a their pivots as a center. spherical curve on the EDGAR D. TILLYER.

2, In a device of the character described, NELSON M. BAKER. 

